Irish authorities are liaising with Polish officials over the source of the contamination.
Traces were found at Rangeland Foods in Co Monaghan, owned by ABP Food Group.
The Group has lost contracts with:
- Co-Operative Group
- Burger King
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The significant development came after a forensic re-examination of a palm print left on a getaway vehicle.
Carla Lane was once one of the UK's highest paid screenwriters.
Politicians, royalty and the descendants of combatants in the Battle of Jutland commemorated the 8,648 seamen who died in the engagement.